Recently, the world's leading companies as well as domestic companies are actively carrying out the research and production for flat display devices. The display industry is a future oriented industry with the high market value enough to designate as one of the world's 10 next-generation growth engine industries.
The flat display devices may typically include plasma display panels, liquid crystal displays, light emitting devices.
The liquid crystal displays are a leading device of the display industry. The companies and the academies have been making the effort for increasing the quality and the cost competitive power on all sort of components used in the liquid crystal displays.
The liquid crystal display may include a backlight unit producing light, a thin film transistor controlling a movement of a liquid crystal, and various optical sheets and panels capable of diffusing, focusing, and reflecting the light produced by the backlight unit.
The optical sheet may be applied to all sort of display devices as well as the liquid crystal displays. The optical sheet may include a reflective sheet, a polarization sheet, a diffusion sheet, a prism sheet, and so forth.
The optical sheet has a thickness of several micrometers to several hundred micrometers and is very weak to foreign substance and a physical pressure. Therefore, before the optical sheet is used as a component of all sort of display devices, protective films may be attached to both surfaces of the optical sheet so as to protect the optical sheet.